From 0eeb5a3b586a1caed724ce93be39749c0eaf58ee Mon Sep 17 00:00:00 2001
From: Minggang Wang <minggangw@gmail.com>
Date: Thu, 15 Jan 2026 13:17:48 +0800
Subject: [PATCH 1/2] Fix race condition causing crash when setting content
 filter during spin

---
 src/rcl_subscription_bindings.cpp        | 10 +++++++---
 test/test-subscription-content-filter.js |  8 ++++++++
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/src/rcl_subscription_bindings.cpp b/src/rcl_subscription_bindings.cpp
index 78bcd333..06f2f30a 100644
--- a/src/rcl_subscription_bindings.cpp
+++ b/src/rcl_subscription_bindings.cpp
@@ -283,18 +283,22 @@ Napi::Value SetContentFilter(const Napi::CallbackInfo& info) {
     free(argv);
   }
 
+  std::string error_string;
+  if (ret != RCL_RET_OK) {
+    error_string = rcl_get_error_string().str;
+    rcl_reset_error();
+  }
+
   rcl_ret_t fini_ret =
       rcl_subscription_content_filter_options_fini(subscription, &options);
 
   if (ret != RCL_RET_OK) {
-    std::string error_string = rcl_get_error_string().str;
-    rcl_reset_error();
     Napi::Error::New(env, error_string).ThrowAsJavaScriptException();
     return env.Undefined();
   }
 
   if (fini_ret != RCL_RET_OK) {
-    std::string error_string = rcl_get_error_string().str;
+    error_string = rcl_get_error_string().str;
     rcl_reset_error();
     Napi::Error::New(env, error_string).ThrowAsJavaScriptException();
     return env.Undefined();
diff --git a/test/test-subscription-content-filter.js b/test/test-subscription-content-filter.js
index 5660324a..4d58f651 100644
--- a/test/test-subscription-content-filter.js
+++ b/test/test-subscription-content-filter.js
@@ -295,7 +295,10 @@ describe('subscription content-filtering', function () {
         const contentFilter5 = {
           expression: 'data = 5',
         };
+        // Stop spinning before changing content filter to avoid race condition
+        this.subscriberNode.stop();
         subscription.setContentFilter(contentFilter5);
+        this.subscriberNode.spin();
         resolve(msgCnt);
       }, SUBSCRIBER_WAIT_TIME)
     );
@@ -304,6 +307,7 @@ describe('subscription content-filtering', function () {
 
     const p2 = new Promise((resolve) =>
       setTimeout(() => {
+        this.subscriberNode.stop();
         resolve(!fail && msgCnt5 && !msgCnt0);
       }, SUBSCRIBER_WAIT_TIME)
     );
@@ -364,7 +368,10 @@ describe('subscription content-filtering', function () {
     const p1 = new Promise((resolve) =>
       setTimeout(() => {
         const result = !msgCnt0 && msgCnt5 && !fail;
+        // Stop spinning before changing content filter to avoid race condition
+        this.subscriberNode.stop();
         subscription.setContentFilter();
+        this.subscriberNode.spin();
         resolve(result);
       }, SUBSCRIBER_WAIT_TIME)
     );
@@ -374,6 +381,7 @@ describe('subscription content-filtering', function () {
 
     const p2 = new Promise((resolve) =>
       setTimeout(() => {
+        this.subscriberNode.stop();
         resolve(msgCnt0 && msgCnt5 && !fail);
       }, SUBSCRIBER_WAIT_TIME)
     );

From 1de4f4b9fbe06f8b953b91beca9988ae28c3d7d3 Mon Sep 17 00:00:00 2001
From: Minggang Wang <minggangw@gmail.com>
Date: Thu, 15 Jan 2026 13:57:48 +0800
Subject: [PATCH 2/2] Address comments

---
 src/rcl_subscription_bindings.cpp        | 2 +-
 test/test-subscription-content-filter.js | 2 --
 2 files changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/rcl_subscription_bindings.cpp b/src/rcl_subscription_bindings.cpp
index 06f2f30a..2f5ee251 100644
--- a/src/rcl_subscription_bindings.cpp
+++ b/src/rcl_subscription_bindings.cpp
@@ -283,7 +283,7 @@ Napi::Value SetContentFilter(const Napi::CallbackInfo& info) {
     free(argv);
   }
 
-  std::string error_string;
+  std::string error_string = "";
   if (ret != RCL_RET_OK) {
     error_string = rcl_get_error_string().str;
     rcl_reset_error();
diff --git a/test/test-subscription-content-filter.js b/test/test-subscription-content-filter.js
index 4d58f651..099b4ae1 100644
--- a/test/test-subscription-content-filter.js
+++ b/test/test-subscription-content-filter.js
@@ -307,7 +307,6 @@ describe('subscription content-filtering', function () {
 
     const p2 = new Promise((resolve) =>
       setTimeout(() => {
-        this.subscriberNode.stop();
         resolve(!fail && msgCnt5 && !msgCnt0);
       }, SUBSCRIBER_WAIT_TIME)
     );
@@ -381,7 +380,6 @@ describe('subscription content-filtering', function () {
 
     const p2 = new Promise((resolve) =>
       setTimeout(() => {
-        this.subscriberNode.stop();
         resolve(msgCnt0 && msgCnt5 && !fail);
       }, SUBSCRIBER_WAIT_TIME)
     );